davideggy:However, I'm guessing the same problem arises when applying that line of reasoning to a lot of multi-superhero universes.

Like the way supervillains habitually only ever attack one city, and in that city almost always face the same superhero? Or the way that superheroes routinely insist on facing the one villain whose power is most dangerous to them?

I hold out hope for the storyline where Iron Man gets on the phone and says "Human Torch? Hi! Iron Man here. Listen, could you pop over and take care of The Melter for me? And in return, I'll step in next time Firehose Man comes looking for you."